Differential feeding mechanism for sewing machines



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R. R. HUGHES. JR DIFFERENTIAL FEEDINGKMECHANI SM FOR SEWING MACHINES Original Filed 001:. 1'7 1919 2 Sheats-Sheqt 1 Dec. 25, 1923.

R. R. HUGHES. JR DIFFERENTIAL FEEDING MECHANISM FOR SEWING MACHINES,

Original Filed Oct. 17, 1919 2 Sheets-Sheet 2 Q I I alibo'mmvS Patented Dec. 25, i923.

ETATEfi earner onion.

ROBERT E. HUGHES, 3B, OF UI'ICA, NEW YORK, ASSIGNOR T0 UNION SPECIAL IVIA- v CHINE COIVIIANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

DIFFERENTIAL FEEDING MECHANISEI .FQB SEVIING- LIACHINES.

=0rigina1 application filed 0ctofoer17, 1919, Serial No. 331,312. Divided and this application filed .Tune 9,

1920. Serial No. 387,631.

To aZZ whom it may concern:

Be it known that I, ROBERT R. HUGHES,

Jr., a citizen of the United States, residing at Utica, in the county of Oneida, State of New York, have invented certain new and useful Improvements in Differential Feeding Mechanism for Sewing Machines, of which the following is a description, reference being had to the accompanying drawing and to the figures of reference marked thereon.

The invention relates to new and useful improvements in feeding mechanisms for sewing machines and more particularly to a feeding mechanism used in connection with a work supporting arm on to which or off from which the material is fed during the stitching operation.

An object of the invention is to provide a feeding mechanism having a main feed dog and laterally spaced auxiliary .feed dogs, together with independent means for actuating the auxiliary feed dogs whereby their movements may be independently varied relative to the movements of the main feed dog.

' A further object of the invention is to provide a feeding mechanism of the above character wherein the auxiliary feed dogs receive their feeding movements from the main feed bar actuating the main feed dog.

These and other objects will in part be obvious, and will in part be hereinafter more fully disclosed.

In the drawings which show by way of illustration one embodiment of the invention:

Figure 1 is a view in section longitudinally of the work supporting arm showing a portion of a machine embodying my improvements;

Fig. 2 is a top plan view partly in section of the same; and

Fig. 3 is a detailed view showing a portion of the feeding mechanism from the opposite side of the machine from that viewed in Fig. 1.

The invention in its broadest aspect consists of'a feeding mechanism having a main feed dog and two auxiliary feed dogs which are independently mounted and receive their I feeding movements through independently actuated devices capable of adjustment the same feed bar so far as vertical move ments are concerned, and are raised and lowered by one actuating lever. The auxiliary feed dog at one side of the main feed bar is connected to a rock arm which is oscillated by the main feed bar and the connection between the rock arm and the main feed bar is capable of adjustment so that the throw or endwise movement of the auxiliary feed bar may be varied. At the other side of the main feed bar is another auxiliary bar carrying a second auxiliary do and this auxiliary bar is likewise operate by an arm which is oscillated by. means of a connection with the main feed bar and this ings, is shown as applied to a machine of the ty e described in my copendin application, erial Number 331,312, filed October 17, 1919, of which the present application is 7 a division. Said machine includes a supporting base 1 having a standard 2 from which projects a suspended work supporting arm 3. Also mounted on the standard 2. is an overhanging armd carrying the needle mechanism, and also carrying the presser foot which is indicated at 5. The material is fed endwise of and preferably on to the work support by means of a main feed dog 6,-and two auxiliary feed dogs'i'and 8; The main feed dog 6 is carried by a main feed bar 9. This main feed 1 bar 9 has a slot at its rear end adapted to engage a pin; 10. carried by a bracket 11, whichjbracket is pivoted at 12 to thework supporting arm. Said braoket11 has an arm l3projecting into the standard 2. An eccentric strap 14 is connected at its lower. end to the free end of this arm 13 and said eccentric strap cooperates with an eccentric 15 on the main shaft 16. The main feedbar 9 is moved endwise for giving the feeding movements to the feed dog. Gbymeans of a link 17 which is pivoted at 18 to'the main feed bar 9. The other end of this link is pivoted to a bolt 19 which is adjustable. in the slot '20 formed in the bracket 11.

This slot is,

so disposed that the pivot bolt 19 may be moved toward and from the fulcrum or pivot point ofthe bracket 11. As the eccentric on the main shaft rotates, it will oscillate the bracket and through this link will impart'endwise movements to the main feed bar. Theextent of the endwise movement is determined by the position of the pivot bolt 19 in the slot 20. The forward end of themain'feed bar is raised and lowered by means of a lever 21 which is pivoted at 22 to a bracket carried by the work supporting arm. The inner end of the lever 21 extends into thestandard 2 and is pivotally connect ed to an eccentric strap 23 cooperating with an eccentric on the main shaft 16. The forward end of the lever 21 is connected to links 24 which in turn are pivoted to suitable pivot bolts 25 projecting laterally from the main feed bar. As this lever 21' is oscillated, the forward end of the main feed bar will be raised and lowered.

The auxiliary feed dog 7 is carried by an auxiliary feed bar 26. This auxiliary feed bar 26 is formed with a slot 27 which straddles" the screw 25. auxiliary feed bar 26 is formed with a. slot 28 which engages a pin 29 on the main feed bar. 'The auxiliary feed bar slides back and forth on these two pins and will be raised and lowered with the main feed bar. The

auxiliary feed bar 26 is moved endwise by means of a pivoted arm 30. Said arm ispivoted at 22 and extends substantially vertically upwardly therefrom. At the upper end of the arm there is a projecting lug 31 towhich a link 32 is pivoted. The other end of this link 32 is pivoted at 33 to the "auxiliary feed bar so that the oscillating movements of the arm 30 will impart end wise movements to the auxiliary feed bar. This arm 30 is oscillated by means of a link 34. Said link 34: is pivotally connected at its left hand end to the screw 25 and is pivotally connected at its right hand end to a screw 35 carried by a block '36 which is adjustable in a radial slot 37 carried by the pivoted arm 30. By shifting this block 36 toward and from the pivotal point of the arm 30, the extent of movement imparted to the arm will be varied. It will be, noted that with the parts'as positioned in Fig. 1, the throw'of the link connected to the auxiliary feed bar is slightly greater than the throw of the main feed bar by reason of the fact that the pivot screw 35 is nearer the pivotal point ofthe' lever 30 than the pivotal connection between the link 32 and said arm.

The auxiliary feed dog 8 is carried by the auxiliary feed'bar 38 located on the other side of the main feed bar 9. This auxiliary feed bar and the means for operating the same is shown in Fig. 3 of the drawings, and is s milar in construction to the means for moving the auxiliary feed bar 26 endwise.

The inner end of the.

Said auxiliary feed bar 38 is moved endwise by a pivoted arm 39 which is connected by a link 40 to the feed bar, and this arm 39 is vibrated by means of a link il connected to one of the screws 25.. Said link ll is pivotally connected to a sliding block'which may be moved endwise in a radial slot 39 formed in the pivoted arm 39; These pivoted arms 30 and 39 are entirely independent of each other and operated by independent connections to the main fee dbar'. The links which vibrate the arms may be set at different points and thus difi'erent throws imparted to the auxiliary feed dogs. The auxiliary feed dogs are widely spaced as clearly shown in Fig. 2 of the 'drawingsyand in certain greater or less as desired, than that of the other.

It is obvious that minor changes indetails of construction and arrangement of parts may be made without departing from the spirit of the invention as set forth in the ap ended claims.

Iaving thus described the invention,

what I claim as new and desire to secure by Letters Patent, is

1 1.-In a sewing'm'achine, a feeding mechanism lncludmg a main feed dog, a main feed bar supporting said main feed dog,

means for moving said feed bar back and forth and up and down for imparting feeding movements to said main feed dog,

'two auxiliary feed dogs associated with said main feed dog means for raising and vlowering the auxiliary feed dogs in timing with the main feed dog, and adjustable independent devices actuated by said main feed bar for imparting feeding movements to said auxiliary feed dog's;

2. In a sewing machineya feeding mechanism including a main feed dog; a main feed bar supporting said main feed dog, means for moving said feed bar back and forth and up and down for imparting. V feeding movements to said main feed dog,

two auxiliary feed dogs associated withcsaid main feed dog, meansfor'raising and lowering the auxiliary feed dogs in timin with the main feed dog, and independent evices actuated by said main feed bar for imparting feeding movements to said auxiliary feed dogs, said independent devices including means whereby the feeding movements of the auxiliary feed dogs may be independently varied.

3. A sewing machine includin in combination a main feed bar, a feed og carried thereby, auxiliary feed bars carried by the main feed bar and mounted to move up and down therewith, an auxiliary feed dog carried by each auxiliary feed bar, devices connected to the main feed bar for moving one of said auxiliary feed bars back and forth, and adjustable independent devices connected to the main feed bar for moving the other auxiliary feed bar back and forth.

4:. A sewing machine including in combination a main feed bar, a feed dog carried thereby, auxiliary feed bars carried by the main feed bar and mounted to move up and down therewith, an auxiliary feed dog carried by each auxiliary feed bar, devices connected to the main feed bar for moving one of said auxiliary feed bars back and forth, and independent devices connected to the main feed bar for moving the other auxiliary feed bar back and forth, said-devices connected to the auxiliary feed dogs including means whereby the feeding movements of the auxiliary feed dogs may be independently varied.

5. A sewing machine including in combination a main feed bar, a feed dog carried v thereby, means for moving the main feed bar back and forth, and means for raising and lowering the front end of said main feed bar, an auxiliary feed bar at each side of said main feed bar and mounted for movement up and down with said main feedv bar and for independent movement endwise of the main feed bar, an auxiliary feed dog carried by each auxiliary feed bar, a pivoted arm at one side of the main feed bar, a link connecting said pivoted arm with the auxiliary feed bar adjacent the same, a link connecting said pivoted arm with the main feed bar, said link being capable of adjustment with said arm for varying the throw of the auxiliary feed bar, a second pivoted arm at the other side of the main feed bar, a link connecting said second arm to the auxiliary feed bar adjacent the same, a link connecting said second arm with the main feed bar for oscillating said second arm, said link having an adjustable connection with said second arm whereby the throw of the auxiliary feed bar actuated thereby may be varied.

6. In a sewing machine, a feedin mechanism including a horizontally Eisposed main feed dog, means for imparting feeding movements thereto, two auxiliary feed dogs co-operating with said main feed dog, and means for imparting feeding movements to said auxiliary feed dogs including devices for independently varying the feeding movements of said auxiliary feed dogs relative to the feeding movement of the main feed dog.

In testimony whereof, I aifix my signature.

ROBERT R. HUGHES, JR. 

